Pyrolytic conversion system

ABSTRACT

A pyrolytic converter utilizing a rotatable drum surrounded by an outer drum support structure and disposed in an oven chamber pyrolyzes materials including plastic waste, tires, materials from automobile shredding operations, containers and trays of plastic material, rubber, leather, garbage, sewage sludge, coal, oil shale, broken asphalt and the like. These materials are formed into cartridges by a compactor using a reciprocating ram which forms cartridges in an injection tube wherein another ram injects the cartridges into the converter drum. The converter is disposed on a fulcrum near the injection end thereof while the discharge end is suspended by cables to accommodate thermal expansion of the converter. Cables also suspend collection and separation apparatus having water filled chutes, into one of which the products of pyrolyzation of low density (char) and solids of higher density are discharged from the converter drum. Lower and higher density solids are separately collected tanks.

DESCRIPTION

Field of the Invention and Related Invention

The present invention relates to pyrolysis conversion systems andparticularly to improvements in pyrolytic converters having a rotatingdrum contained in an outer, stationary structural support andcontainment drum, which provides a substantially air tight region whichis heated by radiation and convection and is disposed in an oven chamberdefined by an insulated external shell, as described in U.S. patentapplication Ser. No. 494,256 filed Mar. 14, 1990 (now U.S. Pat. No.5,082,534, issued Jan. 21, 1992) of which this application is acontinuation in part

This invention is especially suitable for use in the pyrolyticconversion of solid hydrocarbons into gases, liquid hydrocarbons, andchar by the pyrolysis of various materials, such as tires and scrapresulting from the shredding of junked automobiles. The invention isalso useful for pyrolyzing other wastes such as plastic materials,plastic containers and waste from fast food restaurants, garbage, sewagesludge, coal, oil shale, broken asphalt and the like which provides thefeed stock for the converter of system. The above-referenced U.S. Patentshows and describes systems including a plurality of converters. Thisapplication describes a single converter which may be used as one of thestages of a plural stage converter.

BACKGROUND AND ASPECTS OF THE INVENTION

The pyrolytic conversion process requires high temperatures in the 1200°to 1800° F. range in the oven chamber. Then forces due to thermalexpansion, as well as the thermal properties of materials, must beaccommodated in order to achieve satisfactory operation in a commercialenvironment.

The products of pyrolyzation are gases and solids having variousconstituents which determine their volatility and density. The term"gas" as used herein includes non-condensible gases and also vapors(both oil and water vapors). These products are released at hightemperature, which must be reduced in order to condense the gases intotheir liquid constituents and also to collect the solid products.Temperature differentials are required which must be accommodated tohandle thermal expansion especially in the solids collection apparatus.It is also desirable to separate low density and high density solids,for example, char of low density from high density particles, such asfragments of metals and other materials which are not pyrolyzed.

The injection of the feed stock materials presents material handlingproblems, since it is desirable that the injection not introduce airinto the converter (a dangerous condition). It is also desirable toprovide convenient access to the internals of the converter formaintenance and repair and to assemble parts subject to wear so thattheir replacement is convenient.

Accordingly the present invention has the following aspects:

(a) allowance for heat expansion of the converter and also of theexterior casing of the converter, which is both practical and costeffective;

(b) assembling the converter and the apparatus, which handles theproducts discharged from the converter so that thermal expansion andcontraction of the discharge handling apparatus is accommodated;

(c) separating and scrubbing the solids of low and high density, such aschar resulting from the pyrolyzation of hydrocarbons and solids ofmaterial which has not been pyrolyzed, by selective floatation in liquid(water) which also reduces the temperature of these products;

(d) compacting materials to be pyrolyzed so that little or nopreprocessing (comminuting) of these materials (feedstock) is needed andalso so that when injected into the converter drum the feedstockmaterials maintain an air lock in an injector preventing theintroduction of air which might give rise to dangerous operatingconditions in the converter, and eliminating the need to use separatelymade bales or bags of such materials;

(e) condensing and scrubbing the gaseous products of pyrolyzation in amanner to separate hydrocarbon liquids, in accordance with theirvolatility, efficiently and without the need of expensive condensers andto prevent fouling of piping and duct work carrying these gaseousproducts;

(f) operating the converter with bearings and seals utilizing water forcoolant and sealant purposes; and

(g) arranging the components, parts and framework of the converter so asto enable the converter to be fabricated full scale, for example withthe casing including the converter drum and support drum 30 to 40 feetin length and from 6 to 9 feet in diameter and in such a configurationto be operated at temperatures sufficient to pyrolyze feed stockmaterials, such as those mentioned above.

SUMMARY OF THE INVENTION

Briefly described, a pyrolytic converter embodying the inventionutilizes a suspension, which is preferably provided by cables dependingfrom a framework. The suspension provides a fulcrum at one end of theconverter and a pivotal connection via the cables at the other endthereof which accommodates and allows for thermal expansion. Apparatusfor handling the solid products of pyrolysis which are discharged fromthe converter are also suspended, preferably from the discharge end ofthe converter, by cables thereby allowing for thermal expansion. Aburner and associated combustion chamber may also be suspended with theconverter so as to accommodate the thermal expansion thereof. Separationof the higher and lower density products of pyrolysis relies on theirrelative buoyancy The discharge apparatus includes a discharge chute andan adjacent separating (floatation) chute and a discharge conveyor forsolid residues, which contain water at different levels because of theabove atmospheric pressure in the reactor which is communicated to thedischarge chute. Across this water level and interconnecting the chutesis a channel through which a rake is reciprocated which drives thedischarged Products under water and shifts the buoyant materials to thefloatation chute where they float to the surface and can be skimmed off,as by a discharge skimming conveyor. Another conveyor removes theparticles and objects which sink; moving them to a discharge positionabove water level.

The gaseous products are separated in a series of three tanks throughwhich the gaseous products circulate and are condensed in inverse orderof their volatility, in the first, second and third tanks. The secondand third tanks have water circulated therein. In the second tank thewater is converted, by steam and air pressure operated hydraulic means,into a spray for cooling and also scrubbing the gases as they passthrough an inlet pipe into the tank.

The materials to be fed (feed stock) into the converter drum arecompacted into cartridges in a section of an injection tube whichreceives the feed stock from a magazine having an opening in alignmentwith the lower end of a hopper. A gathering ram, with a cover whichcloses the opening, repeatedly moves reciprocally through the magazine,each time gathering additional materials and compacting the materialsinto a cartridge in the section of the injection tube. When thecompacted density is sufficient, a cartridge formed in the section isadvanced by a ram along the injection tube, in the direction of theintroduction end of the converter drum. There the cartridge forms an airlock (with other cartridges). The injection tube and its associatedcompacting apparatus is moveable as a unit through a jacket into the andout of the converter drum. When moved away from the converter drum, anopening or man way is provided, which enables access to the converterdrum for maintenance operations. In such operations, scraper plateswhich are loosely mounted on spring arms may be replaced by moving thespring arms away from the outer periphery of the converter drum toprovide sufficient clearance for the plates to be removed and replaced.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully appreciated from a reading of thefollowing detailed description of a presently preferred embodimentthereof in connection with the accompanying drawings wherein:

FIG. 1 is a right side elevation of a pyrolytic conversion systemembodying the invention;

FIG. 2 is a left side elevation of the apparatus (except for the feedstock lift conveyer) which is shown in FIG. 1;

FIG. 3 is an enlarged right side elevation of the converter system shownin FIGS. 1 and 2;

FIG. 3A is an enlarged view of the region 3A--3A shown in FIG. 3.

FIG. 3B is an enlarged end view of the region shown in FIG. 3A.

FIG. 4 is a rear elevation of the converter system;

FIG. 5 is a top view of the converter system;

FIGS. 5A, B & C are respectively fragmentary plan, left side and rearelevational views of the converter system of the region 5A--5A shown inFIG. 5, showing the combustion unit in greater detail;

FIG. 6 is a sectional view of the feed stock material cartridge formingapparatus taken along the line 6--6 in FIG. 5;

FIG. 7 is a sectional plan view taking generally along the line 7--7 inFIG. 6;

FIG. 8 is a view similar to FIG. 6 with the gathering ram at the end ofits travel towards the left;

FIG. 9 is a view similar to FIG. 7 with the gathering ram in theposition shown in FIG. 8 and with the injection ram advanced towards theconverter drum;

FIG. 10 is a diagrammatic perspective view of the apparatus shown inFIGS. 6 through 9;

FIG. 11 is a fragmentary right side elevation showing the location ofthe apparatus shown in FIG. 10 and injection tube in operating positionin the converter;

FIG. 12 is a view similar to FIG. 11 showing the apparatus shown in FIG.10 removed from the converter;

FIG. 13 is a view of the outer casing of the converter showing theoverlapping or shingled relationship of the panels of the casing's outershell and their stiffening roof strips;

FIG. 14 is a fragmentary sectional view taken

alone the line 14--14 in FIG. 13;

FIG. 15 is an enlarged sectional view in elevation along a verticalplane through the converter apparatus and showing the converter drum,the outer structural support drum and the casing and also showing theinner end of the injection tube and the jacket, seal assembly thereof,the stanchions for journaling the rotary converter drum at the injectionend thereof, the fulcrum supporting the converter and also showing theproduct gas outlet and the discharge chute where they enter theconverter;

FIG. 16 is a fragmentary sectional view taken along the line 16--16 inFIG. 15;

FIG. 17 is a sectional view of one of the stanchions and rollerjournals, which view is taken along the line 17--17 in FIG. 16;

FIG. 18 is an enlarged end view along a plane perpendicular to the axisof rotation of the converter drum showing the scraper mechanism;

FIG. 19 is a front view of a scraper plate;

FIG. 20 is a fragmentary sectional view similar to FIG. 15 showing therear end of the converter and showing the structure for the beams andmembers which connect to the suspension cables;

FIG. 21 is a sectional view taken along the line 21--21 in FIG. 20;

FIG. 22 is a sectional view taken along the line 22--22 in FIG. 21;

FIG. 23 is an enlarged fragmentary view showing the journal and drivesystem at the rear or discharge end of the converter;

FIG. 24 is an enlarged end view of the apparatus for collecting andseparating the solid products discharged from the converter;

FIG. 25 is an enlarged fragmentary side elevation also showing thecollection and separation apparatus and the structure connecting it tothe discharge end of the converter;

FIG. 26 is an enlarged sectional view illustrating the internals of thecollection and discharge apparatus shown in FIGS. 24 and 25;

FIG. 27 is a top view of the product gas scrubbing and condensingapparatus;

FIG. 28 is a sectional view taken along the line 28--28 in FIG. 27;

FIG. 29 is a fragmentary sectional view taken along either of the lines29--29 in FIG. 28; and

FIG. 30 is a perspective view illustrating the product gas condensingand scrubbing apparatus.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, there is shown a pyrolytic converter 10which is supported on the ground, preferably on a reinforced concretebase 12. The apparatus has a frame work or super-structure made up of arear pair 14 of column girders at the discharge end region 16. Thesegirders are bridged by a beam member 18 (see FIG. 4). There is a frontpair of column girders 20 at the introduction end 15 where material tobe pyrolyzed is introduced into the converter 10. These front columngirders 20 are bridged by another beam member 25 (see FIG. 5) whichprovides a base for a fulcrum at which the converter is supported at itsfront end. A truss structure 26 is connected to the column girders 14 &20 on each side thereof, and together with slant struts 28, rigidify thesuper-structure.

A walkway 30 guarded by railings 32 extends alongside the converter. Seealso FIG. 5. Access to the walkway is by way of stairs 34. The stairsalso extend to a walkway 35 adjacent a platform 36 made up of a framemade up of the cross beam 25 and side and end beams 36 which supports agathering and injection mechanism 38 for the feed stock to theconverter, which is delivered to a hopper 40 by a portable lift conveyer42, so that the hopper can be loaded from the front or from the sides ofthe converter 10. The beams 36 are supported on legs 44 and rigidifiedby cross struts 46. The injection mechanism (see also FIG. 10) includingthe hopper 40 is supported on a moveable cradle 48 which enables theinjection tube 50 of the mechanism 38, as well as the entire mechanism,to be shifted between the positions shown in FIGS. 11 and 12, where theinjection tube is inserted into and removed from the converter,respectively. The stairs 34 may continue up to another walkway 35 nearthe top of the hopper 40 so as to provide operator access thereto.

The converter 10 has a casing 52 with an outer shell made up of rows ofpanels 54 which are disposed in overlapping or shingled relationship.Bent panels 56 form the roof of the converter casing. These panels 56are bent so as to be trapezoidal in shape in cross section. Theoverlapping or shingled edges of the panels 54 are as shown in FIGS. 13and 14. These edges run transverse to the axis of the converter. Thebent panels 56 are also shingled along their transverse edges.

A chimney 57 for flue gases extends from the converter near the endregion 15 thereof where the materials to be pyrolyzed are introduced.The solid products of pyrolyzation leave the converter through adischarge chute 306 of a collection and separating apparatus 60. Thegaseous products of pyrolyzation pass via an outlet pipe 62 (see alsoFIG. 5) to a condenser system 64 having three tanks 66, 68 and 70,through which the gases successively pass and are condensed. The tanksrest on a platform 72 on the side of the converter opposite from thestairway 34. A separate walkway 31 with a set of stairs 33 at one endthereof provides access to condenser system 64. The platform 72 issupported on columns 24 connected by cross beams extending between thecolumns 24 along the length and width of the platform. The tanks areconnected by pipes. Uncondensed gas is taken off by a outlet pipe 76which may be connected to a storage tank. The collected gas may be usedto fire a combustion unit 78 which heats the converter to pyrolyzingtemperatures. The noncondensible product gases are methane, propane,etc. and they or natural gas or propane may be used to fire the unit 78.The unit is desirably a forced air or duct burner of the type which iscommercially available. Only the inlet ducting 79 from the combustionunit to the converter is shown in FIGS. 1-4. Excess gas may be flared atthe end of a flare pipe 80 or piped into the combustion chamber of thecombustion unit.

The converter has, within the casing 52, an inner support drum 84 (seeFIG. 15) which is closed by end bulkheads 88 and 90 at the introductionand discharge regions 15 and 16 of the converter, respectively providingwith associated seals, an air tight chamber in which the converter drumis disposed. The converter is structurally integrated by its innersupport drum structure. This integrated support structure rests on thecross beam 25 of the framework at the front end thereof. The rear end issuspended at its rear end from the cross beam 18 by a pivotal suspensionsystem using cables 120 and 122 best shown in FIGS. 3, 4 and 25, anddescribed more fully below. The suspension system uses a pair ofvertical riser plates 265 attached to the front end bulkhead 88. Anotherpair of vertical riser plates 266 are connected to the rear end bulkhead90. The suspension system allows for thermal expansion of the converterassembly.

The front end of the converter rests on the beam 25 in a manner todefine a fulcrum which enables the converter to be tilted at a smallacute angle downwardly from its front end 15 to its rear end 16. Thisangle may be about 6°. FIG. 15 shows the converter drum axis horizontaland the injection tube axis tilted upwardly. It will be appreciated (seeFIGS. 1 and 3) that the converter axis (the axis of the drums 84 and 86)is tilted downwardly and the injection tube axis is horizontal.

The suspension system provides a fulcrum at the upper face of the crossbeam 25 which is horizontal. See FIG. 3A & B. A cross beam 29 isattached as by welding to a plate 167 extending between and welded tothe lower edges of the front end vertical risers 265. Cross struts 269between these risers rigidify the assembly. The cross beam 29 ispreferably a small (e.g. 3"×3"×3/8") square structural steel tube andhas slightly rounded edges, thus providing the fulcrum on the crossbeam's upper surface. Angles 27 may be connected to the plate 167 andact as stops in the remote event that the converter moves off the beam25, as in assembly of the system 10. Stops 311 on the cross beam preventlateral shifting of the converter assembly at its front end 15.

The front or introduction region 15 of the inner drum support structurehas, as best shown in FIGS. 15 and 16, use a pair of laterally spacedstanchions 91 and 92 connected by way of gussets to the inner supportdrum 84 and also connected thereto by welding. The stanchions aretubular and support, on interior sleeves 96 (see also FIG. 17), whichextend upwardly from flanges 98, roller bearing assemblies 100. Theinner converter drum 86 is journaled and rotates on the rollers of theroller assemblies. The outer tube of the stanchions extends to a lowerflange 102 which may be bolted to the flange 98 in assembling thestanchions 91 and 92. The interior of the stanchions define chambers inwhich reservoirs of cooling water are circulated by inlet and outletpipes 104 and 106. Thus, as the converter drum is rotated by a drivemechanism 108 at the rear or discharge end region 16 of the converter,the converter drum rotates on the rollers. A bearing ring 110 isprovided upon which the rollers bear. This ring 110 also stiffens theconverter drum.

The remainder of the support for the converter (the casing and the innerand outer drums and their associated bulkheads and drive mechanisms),and also for the combustion unit, and separating and collectionapparatus 60, is provided by a pivotal suspension of the converter inthe discharge region 16 thereof. Optionally, the combustion unit may bemounted off the converter and connected by a flexible duct (bellows) tothe inlet ducting 79. The suspension and the fulcrum provided by thebeams 25 and 29 provide a pivotal support for the converter. Cables ofsteel wire 120 and 122, provide the main suspension. These wires areconnected to the beam member 18 by means of ears 124 welded to ends ofthe beam member 18, which is disposed above the discharge end of theconverter. See also FIG. 4, 20 and 25. The cables extend to a cross beam126 which is attached to the rear vertical risers 266 and thereby, viathe bulkhead 90, to the inner support drum 84 of the converter (seeFIGS. 3 and 4). Gussets 271 (see FIG. 25) further strengthen theconnection of the risers 266 to the bulkhead 90. A pair of arm members130 are welded to the rear riser 266 and project rearwardly and providesupport for a cable arrangement 132 which cradles the separation andcollection apparatus 60. Accordingly, the entire converter 10, includingits collection and separation apparatus 60, all of which operate at hightemperature and are subject to thermal expansion, are suspended by thepivotal support suspension of the cables 120, 122 and 132 to allow forthermal expansion. As the converter expands, the cables pivot or swingand the converter rocks or tilts slightly on the fulcrum provided by thebeams 25 and 29. For a thirty-two foot long converter and an averageexpansion of about 6 inches, the variation in inclination of the axis ofthe converter is not significant to the pyrolytic conversion process.

As shown in FIGS. 5 and 5A to 5C, the combustion unit 78 is made up of acombustion chamber 81 and a burner 83. The burner is a conventionalforced air burner of the type which is commercially available and has ablower 85. The duct work 79 and the burner 83 are connected to oppositeends of the rectangular combustion chamber. The combustion chamber 81mounted on a platform 89 rests on the beam 126. It is counterweighted atthe opposite end of the beam by a weight shown schematically at 301. Thecombustion chamber provides a residence time for hot combustible gasesincluding any gases which may be vented to the combustion chamberinstead of to the flare 80. If vents are used for pressure relief in gasand oil holding or storage tanks, the vented gases can be returned tothe combustion chamber and burned therein. Thus, the combustion chamberis used to prevent environmentally damaging emissions from the system10.

Referring again to FIG. 15, the injection tube 50 is shown having fourblades 138, 90° apart, with their cutting edges 140 extending inwardlyso as to cut and severe cartridges of the material feedstock which isinjected through the tube 50 by the injection mechanism 38. Theinjection tube 50, as well as the entire mechanism is removable from theconverter as explained above in connection with FIGS. 11 and 12. Tofacilitate this removal, there is provided a tube 144, which is weldedto the introduction end bulkhead 88 on both of its side plates 88a and88b and terminates at a flange 146 (see also FIGS. 11 and 12). A waterjacket 147 is disposed outside of the bulkhead 88 and extends to theflange 146. Another water jacket 150 is disposed around the injectiontube 50 and terminates at its flange 148. Water is circulated throughthese water jackets 147 and 150 to keep the flange and sealstherebetween cool.

Referring to FIGS. 6-10, there is shown the injection mechanism 38. Theinjection tube 50 contains a ram 160 which is driven by an actuatorwhich may be a hydraulic cylinder. The actuator 162 has hydraulic linesconnected to a controller 164. It switches pressure from supply P_(s)(pump pressure) to return P_(R) (reservoir pressure) in response to acontrol signal CPS. CPS originates in the cartridge forming mechanism inresponse to pressure developed in its actuator 166, which may also be ahydraulic cylinder. The pressure switch responds to the back pressure onthe actuator which is a function of the compression of the feed stockmaterial in a section 168 of the injection tube. This section is definedby a magazine 170 which is connected to the platform 48 (see, FIGS. 11and 12) via a frame of eye beams 172 and extends beyond the platform.The actuator 166 is anchored in the rear eye beam 172 and is connectedto a gathering ram or shovel 174, of hemi-cylindrical shape. The shovelis reciprocated by the actuator repeatedly between the position shown inFIGS. 6 and 7 and the position shown in FIGS. 8 and 9. The closedposition is shown in FIGS. 8 and 9. There the shovel closes the section168. A cover 178 moveable with the shovel seals the opening 176. Eachtimethe shovel 174 reciprocates, it picks up more material and furthercompresses the material into a cartridge in the section 168. Acontroller 180 provides for continuous reciprocation by alternating thepressure between P_(s) and P_(R) on opposite sides of the cylinder ofthe actuator 166. The operation of the actuator and of the gathering rammay be stopped by moving the controller to an off position.

A compact cartridge is indicated by an electric or fluid pressure outputsignal CPS from a pressure switch PS. In other words, when the backpressure on the shovel exceeds a predetermined pressure, the pressureswitch PS outputs CPS to the controller 164 of the actuator 162. Then,the actuator 162 is actuated and advances the cartridge by a distanceequal or somewhat greater than the axial length of a cartridge, two ofwhich 182 and 184 are shown in FIG. 10. The leading cartridge is forcedinto the converter drum. While being forced into the drum, it is severedand comminuted by the blades 138. The compact cartridges form an airlock or seal in the injection tube 50. Any air is exhausted throughbleed holes 186. Also, any excess moisture (liquid) flows out throughthese holes, thereby providing an air tight seal against the admissionof air into the converter drum which might cause a dangerous condition.A high temperature seal material between the flanges 146 and 148 is usedto seal the injection end of the converter at the flanges 146 and 148.The water jackets 147 and 150 cool the flanges and their seals.

Referring to FIGS. 15 and 16, it will be seen that the outer stationarydrum 84 has a plurality of longitudinal and circumferential fins 190 and192. The finned side of the outer drum 84 faces the inside shell 194 ofthe casing 52 and is connected thereto by brackets 196. The brackets maybe welded to the casings. All of the drum and casing internal parts maybe stainless steel. An oven chamber 198 is formed between the outer drum84 and the casing 52 which is heated by the burner 78 (see FIG. 21). Asshown in FIGS. 21 and 22, the blast of hot gas is diverted by V-shapedvanes 200 around a section 202 (square in cross section) of thedischarge chute which enters through the outer drum 84 into an endregion past the discharge end 205 of the converter drum 86.

As shown in FIG. 20, the converter drum is connected by way ofcircumferentially spaced rods 204 to a bulkhead 206. This bulkhead has ashaft 208 extending therefrom which is journaled in a water cooledbushing 210 in the discharge end bulkhead 90 of the converter. A crusherrod 212 which is raised and dropped as the converter drum 86 rotates, inthe direction shown by the arrow 214 (FIG. 21) assist in crushing andheating solid material which moves downwardly along the inclined (at anangle of approximately 6° to the horizontal) converter drum 86.

The solid products of pyrolyzation (primarily char) and solid particleswhich have not completely pyrolyzed, drop through the chute 202. Thegaseous products of pyrolyzation exit through the outlet end 205 of theconverter drum 86 along the gap between the converter drum 86 and theinner drum 84, thereby promoting convective heat transfer to theconverter drum from the chamber 198 surrounding the inner drum 84, andthen through the discharge pipe 62 which passes through the forwardbulkhead 88 into a region at the front or introduction end 207 of theconverter drum 86.

A duct 230, which is normally closed, can be opened via a gate 239, torelieve over temperature conditions. When the injection tube 50 isremoved, as to the position shown in FIG. 12, the sleeve 144 provides amanway for access into the converter drum 86. There are also a pluralityof ducts 309, shown best in FIG. 2 and FIG. 15, which are normallyclosed by gates which can be opened and torches attached to maintaintemperature in the oven chamber and prevent cooling and solidificationof the material in the converter drum, should the electrical power fail.

The panels 54 of the outer shell of the casing 52 are connected to theinner shell 194 by Z-shaped struts 240 (See FIGS. 13 and 14). Thesestruts may be welded and define spacers. The space between the strutsand throughout the entire casing 52 is desirably filled with insulation,such as basalt rock wool. The outer panels 54 are exposed to the air andmay heat to 100°-150° F. Expansion is accommodated by the overlapped orshingled relationship of the longitudinal (vertical) edges 242 and 244.These plates 54 may be of thin (1/8 to 1/4 inch) metal such as stainlesssteel and are stiffened by the strips 246 which provide a roof andwindshield over the overlapping edges thereby diverting rain andprotecting against injuries to personnel who might encounter sharp edgesthereof. The strips 246 also control any deflections of the underlyingpanels 54. The strips 246, an exemplary row of panels 54 of the casing52 and arrows 248 indicating the direction of expansion and contractionof the converter (the longitudinal direction along the axis of theconverter) are shown in FIGS. 13 and 14. Fewer panels than shown may beused, and longer shingles or other slipable couplings used.

A scraper mechanism for scraping away residue along the inner peripheryof the converter drum 86 is provided by a rod 250 which is cantileveredby a sleeve 252 connecting the rod 250 to the introduction end bulkhead88 (see FIG. 15 and also FIGS. 16 and 18). This rod extends about twothirds the way from the introduction end 15 towards the rear end 16. Therod 250 has extending therefrom in side by side relationship a series ofwire springs 254, which may be bent in hairpin shape using a loop 256 asshown in FIG. 18. At the end of each spring 254 is a scraper plate 258(see FIG. 19). The scraper plates are disposed end to end as shown inFIG. 15. Each plate has a hole 260 which is larger in diameter than thesprings which extend therethrough. The plates are welded to the springsat the holes. The springs 254 are held in a sleeve 255 by end stops 257and can rotate within the sleeve so as to enable the plates 258 toconform with the inside of the drum 86.

Referring to FIGS. 20 and 23, there is shown the construction of thedischarge end of the converter. It is at the discharge end that themechanism 108 for driving the shaft 208 which rotates the converter drumis disposed. This drive mechanism and the beam 126 and members 130 whichare involved in the cable suspension are supported from the bulkhead 90.This bulkhead 90 has a radial array of gussets (much like spokes of awheel). These gussets are plates extending from a collar 260 around theshaft 208 and spaced radial outward from the journal bushing 210 so asto provide a water jacket through which water is circulated via pipes262 and 264. The bulkhead is filled with insulation (e.g. rock wool)between the gussets. This structurally rigid bulkhead provides supportfor the beam 126 and members 130 by way of the pair of vertical riserplates 266 which are disposed parallel to each other on opposite sidesof the shaft 208. These plates are welded to the rear wall 268 of thebulkhead 90. A platform thereon 274 which supports the drive mechanism108 and a roller bearing assembly 276 is attached to the riser plates266 and between the riser plates 266. The assembly 276 is mounted on ariser 278 which is attached to the platform 274.

The shaft 208 has connected at the end thereof, a sprocket wheel 280 ofa sprocket drive assembly. This sprocket wheel is keyed to the shaft 208and is driven by a motor 282 having a drive sprocket 284 attached to theshaft of the motor. A chain 286 couples the sprockets 280 and 284 anddrives the shaft 208; in turn driving the converter drum 86. It may bedesirable to provide speed reduction and increased torque, enabling useof smaller motor to use a multiple reduction sprocket transmissionbetween the motor and the shaft 208. The motor may be a variable speedmotor to change the rotating speed of the converter drum. A cover 267extends between the vertical struts 266 and a cover 269 over thesprocket drive assembly.

The shaft 208 is water cooled through a coupling 288 provided by aswivel, sealed by O-rings, and which is stationary while the shaftturns. A bore 290 defines a cooling chamber having an inlet pipe 292extending to the forward end of the chamber 290. Water is driven throughthe tube 292 and then circulates back along the bore 290 to an outlet294 at the swivel 288. Further cooling and sealing of the shaft isprovided by a bellows-flange arrangement 298. The forward flange isconnected to the stationary bushing 210 and supports the bellows andrear flange of the assembly 298 in stationary position. A water jacket300 around the shaft 208 in back of the assembly 298 provides a waterseal, as well as cools the shaft 208. High temperature "Garlock" typeseals are used at both ends of the jacket 288.

Referring to FIGS. 24 through 26, there is shown the solid dischargecollecting and separating apparatus 60 which separates the low density(char) from the high density (solid particles) which are discharged atthe discharge end of the converter drum 86. The apparatus 60 isconnected to the discharge chute section 202 (see FIGS. 20 and 21) whichis almost entirely internal of the casing 52. The discharge chute has alower flange which is connected to an upper flange of the dischargechute 306 of the apparatus 60. There may be some flexure in thedischarge chute 306 as the cable suspension 132 pivots with thermalexpansion of the collection apparatus 60.

The cables 132 define a cradle, and may be separate cable strands whichpass under the apparatus 60 and are connected to rings on the members130. Alternatively, there may be rings 308 in pairs on opposite sides atthe base of the apparatus 60. Separate strands of steel wire cable maybe connected to these rings 308 and are threaded through rings 310 whichare connected to the hanger members 130.

The apparatus 60 is an assembly of the discharge chute 306, a floatationchute 312 located along side the discharge chute 306, a heavy solidslift and discharge conveyor 314 and a pusher ram unit 316. The pusherram unit is connected to a housing 318 which defines a channel 320,interconnecting the floatation chute 312 and the discharge chute 306near the bottom thereof. This connection is provided by a series ofstruts 322. The discharge conveyor 314 is contained in a housing 324 andextends from below the level of the chutes 306 and 312 to above thelevel of these chutes as shown in FIGS. 1 and 2 to a discharge point,under which a container for receiving the heavy solid residue particles(not shown) is disposed. The water in the chutes 306 and 312 provides aseal or air lock against the admission of air into the converter.

The conveyor 314 in the housing 324 is a drag conveyor with horizontalflights 328. The solid particles fall between the flight 328 to thebottom of the housing 324 where they are swept by the flights and aredelivered to the discharge position at the top of the housing 324.

A housing 330, is connected to the top of the floatation chute 312 andends along a side 332 off the discharge chute 306. This housing 330contains another chain drag conveyor 334 having flights 336. Theconveyor 334 discharges through the duct 307 connected to the housing330 at the rear end thereof.

As shown in FIG. 26, the floatation conveyor 312 is substantially filledwith water to a level indicated as WL1 (the surface of the water). Thedischarge conveyor is filled with water; however, the level of thesurface of the water in the discharge conveyor 306 (WL2) is below WL1since the discharge chute is in communication with the converter whichis pressurized, for example, from two to four psi above atmosphericpressure. Thus, WL1 is determined by atmospheric pressure and WL2 by thepressure inside the converter 10. The upper (right side) ends of thehousings 330 and 324 are open to the atmosphere while the dischargechute 306 is pressurized.

Level Sensors are shown on the chutes 312 and 306 at the requisite waterlevels, WL1 and WL2 and provide outputs (switch closures) which operatepumps connected to inlet and discharge pipes which circulate cool waterto the apparatus 60 to maintain the water levels at WL1 and WL2 and tomaintain the water temperature in the apparatus 60 (between 100 F. and140 F.). The inlet pipe is connected to the chute 312 just below WL1 andthe outlet pipe is connected near the upper end of the housing 324. Itwill be noted that WL1 is at the conveyor 334 so that the flights 336thereon can skim char (light material) which floats and is more buoyantthan the heavy discharge from the pyrolysis process. The other waterlevel WL2 intersects the channel 320. Char, which floats, stays at orbelow WL2 and is pushed by the ram 340 across the channel 320 into thefloatation chute 312. Some solid particles are advanced by the ram 340,but these drop to the bottom of the chutes and are picked up by theflights of the solids discharge conveyor 314. The ram 340 is cyclicallyactuated (every minute or two) so as to push the buoyant particles intothe floatation chamber where they float to the surface WL1, are pickedup by the flights 336 of the conveyor 334 and delivered to a dischargeposition at the end of the conveyor 334 where a container (not shown)may be located. Both solids discharge conveyors may have fans and ducts331 and 333 (see also FIG. 2) at the high points of their housings tocollect any odors and direct them to the burner for destruction.

Referring to FIGS. 27-30, there is shown the condenser and scrubbingsystem for the gaseous products of pyrolyzation. The three condensingtanks are cylinders which may be five to six feet in height. The upperportion of these tanks have rims which form basins 360 into which wateris introduced via pipes 362. The rims of these basins have slots. Thewater in the basin overflows through these slots along the outsides ofthe tanks and assists in cooling the tanks. A basin underneath the tanks(for example on the platform on which they are supported) or at groundlevel, collects the water which flows out of the basins 360.

The tanks operate at different temperatures. The first tank 66, forexample, receives hot gas through a pipe 364 which descendsapproximately 80% of the height of the tank 66. The temperature of theinlet gases may, for example, be 800° F. The gases leaving the tankthrough a transfer pipe 366 may be at a temperature of about 650° F. Theinlet to the transfer pipe 366 is in a chamber 368 with a lip to preventliquids from leaving with the outgoing gaseous stream and to facilitatecondensation of the vapors. Because of the high temperatures of the tank66, gases which condense in the tank, produce heavy oil, such as tar.This tar may be removed from the tank by piping connected near thebottom thereof as shown at 370.

The transfer pipe 366 is supported by a plate 372 on the top of thesecond tank 68 and then descends downwardly to almost the bottom of thetank above the position of an agitator 374 which continuously mixeswater and sludge collected at the bottom of the tank 68 as the coolinggases condense. The agitation keeps sludge in suspension so that itleaves the tank 68 with the water and can be treated (by conventionalseparation methods). A support structure 378 internal of the tank whichis connected to the transfer pipe 366 and to the support plate 372enables the transfer pipe and the structure associated therewith to beremoved for repair or cleaning, if necessary.

The lower end of the transfer pipe 366 is bent into an elbow 380. Thefree end of the elbow is tapered to form a nozzle 382. A sleeve 384,having an upper end 386 bent at a 90° angle to the axis of the sleeve,extends over the free end of the elbow and the nozzle 382. The bent end386 of the sleeve 384 is positioned in alignment with the downwardlydescending portion of the transfer pipe 366. Water enters the bottom ofthe tank 68 through an inlet pipe 388 and leaves through an outlet pipe390 in a turbulence reducing chamber 392 (see FIG. 29). Turbulent andagitated liquids exist at the bottom of the tank 68. The pressurized gas(due to the above atmospheric pressure in the converter) ascends fromthe nozzle 382 through the sleeve 384 and forms a negative pressure(below atmospheric pressure) causing the water to lift up the sleeve 384and spray through the bent section 386 against the transfer pipe 366thereby precooling the gases flowing there through. Alternatively, waterand oil together can be discharged through the outlet pipe 390 andseparate thereafter. This action is an air lift accelerated by steamwhich is formed as the vapors contact the water at the nozzle 382. Theaction amplifies the turbulent fluids (gas and liquid) and scrubs outthe Particles suspended in the gas steam. As the particles are scrubbed,components which are soluble, dissolve in the water so that they may beremoved upon subsequent treatment. Such components include metal halidesand sulphides which would otherwise be more difficult to remove, becausethey dissolve readily in the hot turbulent water.

The outlet gases are substantially cooled in the condensing tank 68 andmay, for example, be 180° F. when entering a transfer pipe 394 whichdescends into the third condensing tank 70. The reduced temperature inthe tank 68 causes medium oils to condense because of their lowervolatility. Such medium oil is collected at an outlet (not shown) abovethe water outlet 390.

Lighter oils are condensed in the tank 70 where the temperature drops,for example, to 100° F. as measured at the outlet pipe 396. The outletsof each tank are in a chamber 398 and 400 similar to the chamber 368 andwhich perform a similar liquid diverting and condensation facilitatingfunction. In the last tank 70, light oil collects and water iscirculated through an inlet 402 and an outlet 404 in the turbulencereducing chamber 392 thereof. This light oil may be pumped through anupper outlet pipe 406 which enters into the chamber 392.

The gases which are not condensed may go either to the flare tube 80 orto a storage tank where they may be used as a combustible gas in theburner 78 or for other purposes. Agitation is also desirable in the lasttank 70 and an agitator 408 is provided at the bottom thereof for suchpurpose.

The water which is used in the process includes water created in theprocess upon condensation in the tanks (68 and 70) which are operatedbelow 212° F. This water is desirably processed in a system including aclarifier tank, sand filters and water treatment tanks. Especially cleanwater may be obtained with a reverse osmosis system. It is desirable touse the water which is processed, but prior to reverse osmosistreatment, internally in the condensing tanks thereof. The cooling waterfor the seals, jackets, the basins 360 and the like is desirably usedafter it is cleaned by reverse osmosis. Other purification processeswhich provide pure water may also be used, but reverse osmosis ispresently preferred.

From the foregoing description, it will be apparent that there has beenprovided an improved pyrolysis converter. Variations and modificationsin the herein described converter and in various aspects of its design,in accordance with the invention, will undoubtedly suggest themselves tothose skilled in the art. Accordingly, the foregoing description shouldbe taken as illustrative and not in a limiting sense.

I claim:
 1. In a pyrolytic converter in which a converter drum isdisposed in a chamber in which the drum is journalled for rotation, animproved mechanism for supporting said converter which accommodatesthermal expansion when said converter is heated to temperaturessufficient for pyrolyzation of materials introduced into said drum, saidmechanism comprising a support member disposed underneath said chamber,a framework resting at ground level including a suspension memberdisposed above said chamber, means pivotally connecting said chamber tosaid suspension member for supporting said converter with said chamberon said support member as a fulcrum about which said converter pivots inresponse to thermal expansion and contraction of said converter.
 2. Theimprovement according to claim 1 were in said converter drum hasopposite end regions in the vicinity of which the materials to bepyrolyzed are introduced and pyrolyzed materials are discharged,respectively, said support member being disposed underneath said chamberin the vicinity of one of said opposite end regions, and said suspensionmember being disposed above said converter in the vicinity of the otherof said opposite end regions.
 3. The improvement according to claim 2wherein said one of said end regions is in the vicinity of where saidmaterials are introduced and said other of said end regions is in thevicinity of where said materials are discharged.
 4. The improvementaccording to claim 3 were wherein said converter includes means forhandling the material discharged from said drum, and suspension meanspivotally connecting said discharge handling means to said chamber andmaintaining said discharge handling means above said ground level. 5.The improvement according to claim 3 wherein said converter hasdischarge handling means disposed at least in part under the end regionwhere said materials are discharged for collecting said material, andsuspension means pivotally connecting said chamber to said dischargehandling means and also maintaining said discharge handling means abovesaid ground level.
 6. The improvement according to claim 5 furthercomprising a second suspension member projecting longitudinallyoutwardly from said chamber in the vicinity of the end region where thepyrolyzed materials are discharged, said discharge handling meanscomprising a first chute depending from said chamber in dischargereceiving relationship with said converter drum, at least one conveyorupon which material discharged to said chute is received, said conveyorbeing disposed beneath said second suspension member and extending inthe same direction as said second suspension member, said suspensionmeans comprising a cable connected between said second suspension memberand said conveyor.
 7. The improvement according to claim 6 furthercomprising a housing enclosing said conveyor and having a bottom andopposite sides, said cable comprising a plurality of sections defining acradle extending about said opposite sides and said bottom.
 8. Theimprovement according to claim 6 wherein a housing encloses saidconveyor, and said housing is inclined upwardly from said first chuteand has lower and upper ends, a second chute extending upwardly fromsaid lower end alongside said first chute, a second conveyor above saidlower end and extending into said second chute, said second chute beingfilled with liquid to present a liquid surface to said second conveyor,said first chute and at least a portion of said housing in the vicinityof said lower end also being filled with liquid, a liquid filled channelabove said housing interconnecting said first and second chutes belowthe surface of said liquid, and a rake reciprocable across said firstchute through said channel to said second chute for moving materialdischarging through said first chute into said second chute forfloatation to said surface for engagement by said rake for removal bysaid second conveyor.
 9. The improvement according to claim 3 whereinsaid framework comprises a first pair of columns resting at said groundlevel and bridged by a first beam providing said suspension member, asecond pair of columns also resting at said ground level and bridged bya second beam providing said support member, said chamber having a barresting on said second beam and being pivotable thereabout to define,said fulcrum.
 10. The improvement according to claim 9 wherein saidchamber has connected thereto a support assembly which comprises a pairof generally vertical plates having upper and lower ends, and meansconnecting said bar to said plates along the lower ends thereof.
 11. Theimprovement according to claim 3 wherein said pivotally connecting andsupporting means comprises a pair of cables each connected to saidchamber on opposite sides of said chamber.
 12. The improvement accordingto claim 1 comprising a beam extending parallel to said suspensionmember, said beam being attached to said chamber in said other of saidend regions, the cables of said pair of cables being spaced from eachother and extending between said suspension member and said beam. 13.The improvement according to claim 12 further comprising means forhandling material discharged from said converter drum, said chamberhaving arm members projecting from said chamber away from said drum andattached to said chamber, and suspension means for suspending saiddischarge handling means from said chamber, said suspension meansincluding a second cable attached to said arm members, said second cablebeing disposed inwardly of said cables from said suspension member tosaid chamber.
 14. The improvement according to claim 1 wherein saidchamber comprises an outer stationary drum disposed around saidconverter drum, a casing around said outer drum defining an oven chambertherebetween, said casing having an inner shell and an outer shell, saidouter shell extending in a longitudinal direction along the axes of saiddrums, said outer shell comprising a plurality of plates having edgeswhich extend transversely to said longitudinal direction in overlappingrelationship.
 15. The improvement according to claim 14 furthercomprising strips having roof sections and having lips along one edgethereof, said lips being connected to each of said plates adjacent andsaid roof section projecting over said overlapping edges, said stripsstiffening said plates.
 16. The improvement according to claim 14further comprising support members connecting said inner shell to saidouter drum, and spacers connecting said plates to said inner shell inspaced relationship therewith, insulating material disposed between saidinner and outer shells.